1. ไป- to go.
2. ต้อง - auxiliary verb "must..." "need to/has to...".
I'm including a lot of verb stuff, it seems, and less nouns or other parts of speech. I feel like in many regards, in the most survivalist aspect of communication, you can get by without nouns better than verbs. Pointing, acting or drawing can all convey what THING you need or want or are talking about. This in combination with the appropriate verb will go an excellently long way toward conveying your meaning to someone.
This is wonderfully, greatly, especially so with a language like Thai (or Chinese). Since they don't conjugate their verbs (or over-abuse them like test tube born lab rat experimental overworked sweat shop hamsters on wheels; really difficult stuff) like they do in Russian, we can get tons of mileage from one single Thai verb. Have we discussed this? I think maybe so. Whether you did it or I did or they did, no matter if it was last year or tomorrow or just recently or in what condition, the verb itself rarely changes. Most often what changes is the stuff around it: words like "today" or "yesterday" or "last year" will indicate exactly when something happened, and the pronouns will indicate the subject and object. This means that a few really useful verbs accompanied by two or three really useful auxiliary verbs already enables the speaker to convey an enormous amount of meaning that might be much more complicated in other languages. This is great; I'm gonna work that verb angle with Thai.